DISCUSSION WITH DRS. OETKEN, DANULAT, AND HUBMANNOF LURGI
The Lurgi Company is the only group with whom we talked that is doing work on pressure gasification. Lurgi recognizes the difficulties of adapting the present process to the production of synthesis gas because of the presence of methane which acts as a diluent. Consideration is being given to minimizing methane by running with a hotter fuel bed at the top. It is planned to accomplish this by putting coal and part of the oxygen in through a vortex at the top of a conventional Lurgi. The top size of coal will be 1/4” and it is hoped that the caking tendency can be reduced to an acceptable degree by this pretreatment in the vortex. No work has yet been done on this modification of the Lurgi but an experimental program is being planned.
Hubmann expressed his opinions on the underlying philosophy of gasification process development. He would prefer to avoid pulverization and to develop a slagging process. He is, of course, a proponent of pressure gasification. In a dust gasification process, Hubmann believes that low carbon conversation need not necessarily be a disadvantage provided there were a use for the residue for other combustion purposes. The ideal synthesis gas process in Hubmann’s opinion would, therefore, operate under pressure with more suitable methods of introducing coal and removing ash. The process would use any type coal without pulverization and would produce a gas containing low concentration of methane.
In discussions with Lurgi it was brought out that the low oxygen consumption of the Lurgi which is due chiefly to the exotherm of the methane formation were reduced either in the unit itself or by reforming in a separate unit.
In discussing gasification reactions, Hubmann pointed out that the cracking of hydrocarbons from the volatile matter is undesirable because the carbon black formed does not react readily with the gasifying medium. Avoidance of this difficulty is one of the major problems of dust gasification processes particularly when the oxygen and coal are fed together and react to form a high temperature zone into which coal is injected.